Heating device



T T E N N E B G Q HEATING DEVICE Filed Aug. 4, '1947 INVENTOR.

44 ATTORNEYJ.

Patented Nov. 28, 1,950

l 2,531,548 HEATING DEVICE Owen G. Bennett, Baltimore, Md., assigner to Catalyst Research Corporation, Pittsburgh, Pa., a corporation of Maryland ApplicationAugust 4, 1947, Serial No. 766,020

1 Claim.

l This invention relates to' apparatus for heating milk, Water and other materials by replaceable cartridges of ignitable material.

Heaters of this type are useful particularly when traveling under conditions in which gasg coal, electricity and other customary sources of external heat are diiiicult to procure. A number of heaters have been suggested which, for the most part, may be divided into two separate types, the first being cartridges, or cartridge-A containing devices which are adapted to be immersed in a liquid and ignited, While the second includes specially constructed food-containing cans which have a space for a cartridge or loose ignitable material. specialized heaters is that they must be used to heat either a liquid or a can and cannot be used for both purposes. Further, particularly With the can heaters, the ignition usually is achieved by use of a fuse, and this method has been found to be inconvenient and often not dependable. Also, the fuse projects out of the container, and, when it has been burnt, it leaves an opening through which the generated heat can escape and cause injury.

It is therefore among the objects of this invention to provide apparatus for heating milk, water or other materials which is inexpensive, safe, easy to operate and dependable in its operation, and which can be used for heating either contained or uncontained materials.

rThe apparatus of the invention is formed of a casing which is provided with a heat conducting Wall forming a chamber in which the material to be heated is placed. Adjacent to that chamber, the casing is provided with a compartment Which has an open end for receiving the heating element, or cartridge, and a cartridge firing mechanism, which includes a block provided With a -movable firing element, is removable. The ring element is spring pressed in one .direction or another, preferably towardthe cartridge, and when so pressed the iiring is accomplished by retracting the element to compress the spring and then releasing it. The heat which is generally by the ignitable material in thecartridge is conducted through the Walls of the casing and into the material-heating chamber.

The preferred embodiment of the invention is illustrated in the accompanying drawings, of which Fig. l is a plan view, and Fig. 2 a vertical section on the line II-II of Fig. 1.

Before describing the apparatus in detail, it should be pointed out that the preferred cartridge or heating element used in it is fully de- One dimculty with these...

2 scribed in my copending application Serial No. 648,980, now Patent 2,500,980, Mar. 14, 1950. Re-

-ferring to Fig. 2 hereof, it consists of an elongated tubular heat conducting member l having a top opening which is hermetically sealed by a closure member 2 that is provided centrally with a percussion primer, or cap 3. The bottom of the closure member 2 rests against a seat, or shoulder 4, formed interiorly at the top of the cartridge, and member 2 -is secured in place to provide the desired sealing by spinning or other- Wise forcing the top rim 6`of tubular member I over the closure member. If desired, a sealing gasket may be disposed between the top rim of the tubular member and the closure member. The tubular member, or container, preferably is constructed of a metal of good heat conductivity, most suitably aluminum or magnesium, or

their alloys, although it will be understood that other metals may be used, such for example, as copper, iron and steel. For most purposes, it is preferred that the cross section of the chamber of the container be small relative to its length because thereby more rapid heat transfer is effected.

A combustible chemical composition 'i is hermetically sealed within the container, such composition comprising at least one oxidizing and one reducing agent. Examples of suitable reducing agents are finely divided metals, such, for example, -as aluminum, zinc, nickel, antimony, and their alloys, as Well as various intermetallic compounds, and a Wide variety of oxidizing agents which may be used include the permanganates,

the chlorates and perchlorates, inorganic oxides and peroxides, the chromates, as well as sulfur and other elements that will combine eXothermically With metals. These materials, and particularly the metals, should be in iinely divided condition, and for most purposes, it is preferred to compact them in the container under rela- .tively high pressure to insure complete combustion of the charge.

When proportioned stoichiometrically, the compositions are productive substantially Wholly of solid products of combustion, and they liberate no appreciable amount of gaseous products. Preferably the container is not Wholly filled so as to avoid the possibility of expansion breaking the hermetic seal when the composition is ignited. One particular advantage of such a cartridge is that the hermetic seal is maintained during the ignition so that the extreme heat which is generated cannot escape and thereby cause possible injury.

The heating apparatus of this invention includes a casing I I of cvoid section which is made from a metal of high heat conductivity, such as those previously mentioned for forming the tubular member of the cartridge. The casing II is provided with a chamber I2 and a cartridge-receiving compartment I3 separated from the chamber by a heat conductingr wall Iii. In operation the chamber receives the material to be heated which may be either canned foodstuff, ik

water for shaving or for sterilizing, or bottles, such as infants milk bottles, In heating mill; bottles, cans, or the like, it is best to use a small amount of water in the chamber, the amount being sufficient to rise substantially to the top of the chamber when the container is set in place.

Compartment I2 is for-med to receive both the autogenous heating cartridge and the cartridge ring mechanism, generally indicated by numeral L i5. Such mechanism includes a block, or barrel, i? provided with a central opening, or bore, i8, in which is movably mounted a firing element, or plunger, I9, the upper end of which projects out of the barrel and 4is provided with a knob 20. The barrel is vfitted into the compartment and is provided exterior-ly with threads `2! which engage threads formed on the interior of the compartment so. as to ber removably received therein, and the upper portion of the barrel is enlarged to provide a flange 22 which is adapted to fit tightly against the upper edge of the compartment.

The upper portion of central bore` I8 is dimensioned tov fit closely about the plungerv and the remainder of the bore increased in diameter to form shoulder 23 on its interior. Also the lower end of plunger I9 is enlarged into approximately the diameter of the main portion of the bore to form a head 24 which carries at its tip a firing pin 2S aligned with percussion cap 3 of the cartridge. To achieve. the necessary percussion force, a coil spring 2'I is placed in the bore about the plunger and bears at one end against interior shoulder 23 and at its other end against the head of the plunger. sion spring which yieldably urges` the head toward the cartridge.

In the operation of the apparatus, a cartridge is rst dropped into the compartment and then firingmechanism it screwed tightly in on top intoA chamber I2 and the bottle placed therein. y,

The plunger then isk pulled upwardly by knob 20 to compress the Spring, and is then releasedfto permit the spring t0, move it downwardly to ignite the material in the cartridge. The Warming takes an unusually short time, after which thev bottley is removed and, if desired, the apparatus prepared for a succeeding heating by removing the firing Preferably, this is a compresmechanism and replacing the spent cartridge. No mechanism is shown for ejecting the cartridge, although, if such be desired, it can be provided by any of the Well-known ejectors.

As previously stated, the invention is not limited to warming bottles or cans but, in addition, may be used to heat water for sterilizing or shavingor any other uncontained liquid.

According to the provisions of the patent statutes, I have explained the principle and construction of my invention and have illustrated andl described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claim, the invention may be practiced otherwise than as specically illustrated and de- SQrbed.

I'claim:

Apparatus for heating milk, water and other materials by replaceable hermetically-sealed cartridges of ignitable material, comprising a casing provided with a heat-.conducting wall forming a vertical open-ended chamber for receiving materials to be heated and provided with a vertical cartridge-receiving compartment in heat-conducting relationship With said chamber wall, the upper end of ,said compartment being open for receiving a cartridge of ignitable material, and cartridge firing mechanism removably positioned in and closing said upper end, said mechanism comprising a barrel provided with a central bore having a a shoulder at its upper end, a ring plunger movably mounted in said bore and having its upper end extending outwardly through saidl block and its lower end enlarged to approximately the diameter of the bore, a ring pin carried centrally at, the lower tip of said plunger, and a spring disposed between said shoulder and said enlarged lower end of the plunger, said spring yieldably urging said pin toward cartridge' rne position..

OWEN G. BENNETT.

REFERENCES CITED The following references are of record in the rile of this patent:

UNITED STATES PATENTS 

